(CNN) --The Bush administration began planning to use U.S. troops to invade Iraq within days after the former Texas governor entered the White House three years ago, former Treasury Secretary Paul O'Neill told CBS News' 60 Minutes.

"From the very beginning, there was a conviction that Saddam Hussein was a bad person and that he needed to go," O'Neill told CBS, according to excerpts released Saturday by the network. "For me, the notion of pre-emption, that the U.S. has the unilateral right to do whatever we decide to do, is a really huge leap."

O'Neill, who served nearly two years in Bush's Cabinet, was asked to resign by the White House in December 2002 over differences he had with the president's tax cuts. O'Neill was the main source for "The Price of Loyalty: George W. Bush, the White House, and the Education of Paul O'Neill," by former Wall Street Journal reporter Ron Suskind.

The CBS report is scheduled to be broadcast Sunday night; the book is to be released Tuesday by publisher Simon & Schuster.

Suskind said O'Neill and other White House insiders gave him documents showing that in early 2001 the administration was already considering the use of force to oust Saddam, as well as planning for the aftermath.

Suskind cited a Pentagon document titled "Foreign Suitors For Iraqi Oilfield Contracts," which, he said, outlines areas of oil exploration. "It talks about contractors around the world from ... 30, 40 countries and which ones have what intentions on oil in Iraq."

In the book, O'Neill is quoted as saying he was surprised that no one in a National Security Council meeting asked why Iraq should be invaded.

"It was all about finding a way to do it. That was the tone of it. The president saying 'Go find me a way to do this,'" O'Neill said.

Suskind also described a White House meeting in which he said Bush seemed to waver about going forward with a second round of tax cuts.

"Haven't we already given money to rich people... Shouldn't we be giving money to the middle?" Suskind says Bush asked, according to what CBS called a "nearly verbatim" transcript of an economic team meeting Suskind said he obtained from someone at the meeting.

O'Neill also said in the book that President Bush "was like a blind man in a roomful of deaf people" during Cabinet meetings.

One-on-one meetings were no different, O'Neill told the network.

Describing his first such meeting with Bush, O'Neill said, "I went in with a long list of things to talk about and, I thought, to engage [him] on. ... I was surprised it turned out me talking and the president just listening. It was mostly a monologue."

"We appreciate his service, but we are not in the business of doing book reviews," he told reporters. "It appears that the world according to Mr. O'Neill is more about trying to justify his own opinion than looking at the reality of the results we are achieving on behalf of the American people. The president will continue to be forward-looking, focusing on building upon the results we are achieving to strengthen the economy and making the world a safer and better place."

A senior administration official, who asked not to be named, expressed bewilderment at O'Neill's comments on the alleged war plans.

"The treasury secretary is not in the position to have access to that kind of information, where he can make observations of that nature," the official said. "This is a head-scratcher."

Even before the interview is broadcast, the topic became grist for election-year politics.

Former Vermont Gov. Howard Dean, who is the early front-runner for the Democratic presidential nomination, issued a statement in response.

"I've always said the president had failed to make the case to go to war with Iraq," Dean said. "My Democratic opponents reached a different conclusion, and in the process, they failed to ask the difficult questions. Now, after the fact, we are learning new information about the true circumstances of the Bush administration's push for war, this time, by one of his former Cabinet secretaries.

"The country deserves to know -- and the president needs to answer -- why the American people were presented with misleading or manufactured intelligence as to why going to war with Iraq was necessary."

Democratic Sen. John Kerry of Massachusetts also issued a statement. In 2002, Kerry voted to support a resolution giving Bush authority to wage war against Iraq if it didn't dismantle its presumed illegal weapons program.

"These are very serious charges. It would mean [Bush administration officials] were dead-set on going to war alone since almost the day they took office and deliberately lied to the American people, Congress, and the world," Kerry said. "It would mean that for purely ideological reasons they planned on putting American troops in a shooting gallery, occupying an Arab country almost alone. The White House needs to answer these charges truthfully because they threaten to shatter [its] already damaged credibility as never before."